"... as the menagerie of young planetary systems grows, researchers are struggling to square their observations with current theories on how our Solar System and others formed. Such ideas have been in turmoil ever since astronomers started discovering planets around distant stars — a list that now numbers in the thousands. The Solar System has rocky planets near the Sun and giant gas balls farther out, but the panoply of exoplanets obeys no tidy patterns. And the rule book for world-building is getting more complicated as researchers find evidence of planets in the process of being born. Still, astronomers hope that witnessing such birth pangs will shed light on how all planetary systems, including our own, came to be. “We see all kinds of structure in these disks, even at very young ages,” says Follette. “Even younger than we classically thought planets should form.”

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"As if theorists did not already have enough to grapple with, observations of planetary nurseries continue to pile up. The latest findings lend weight to the idea that planets are forming early in the lives of their stars, and at distances from them that vary widely.

"And it’s not just ALMA that’s been supplying images. Astronomers have also turned to the SPHERE instrument mounted on the ESO’s Very Large Telescope. This, too, is in the Atacama desert, about a six-hour drive south of ALMA. SPHERE has a system that can cancel out the blurring effects of the atmosphere and a filter that blocks starlight. In April, astronomers announced that they had used it to capture a diverse array of disks around eight young Sun-like stars2. Some resembled wide platters, some had distinct racetrack-like ovals, and one resembled a galaxy with jets streaming from its centre. Such diversity suggests that planet-forming is a complex process yielding many possible outcomes.

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"With the observation of protoplanetary disks still in its infancy, the full story of planet-making will probably be more complicated than anyone expects, and ideas could well be overturned and then overturned again. “Case in point, it looks like the Solar System isn’t even the most common-looking system out there. We’re a little weird,” says Clement. “It turns out there is a lot of complexity out there.'”

Comment: More of the same. Our planet is very different and very special and so is our Galaxy. God the designer/creator at work